<![CDATA[Do QGrahpicsItems need to be dynamicall allocated?]]>I'm working on porting my PyQt app to C++, I've always run into a few bumps here and there, but for the most part it's been pretty smooth. The app makes heavy use of the QGraphicsView Framework.

So let's say I had an object "A," that is a sublcass of "QGraphicsObject," A has a method ".size()," which will return a QSize. It also has some calls to qDebug() in its constructor.

When I made a static instance of A (identified by "b,"), I didn't see any output on the terminal and I got an error like this:

@main.cpp:22:4: error: request for member ‘info’ in ‘b’, which is of non-class type ‘A()’
b.size();
@

When I did a dynamically allocated instance, it worked fine and I saw a message on the terminal.

Can someone explain what's up with this here?

]]>https://forum.qt.io/topic/47437/do-qgrahpicsitems-need-to-be-dynamicall-allocatedRSS for NodeSun, 20 Sep 2026 18:23:51 GMTSun, 26 Oct 2014 00:56:38 GMT60<![CDATA[Reply to Do QGrahpicsItems need to be dynamicall allocated? on Tue, 28 Oct 2014 22:11:20 GMT]]>It might be because I forogt to add the "explicit," keyword to my constrcutors. My Bad....

]]>https://forum.qt.io/post/249316https://forum.qt.io/post/249316Tue, 28 Oct 2014 22:11:20 GMT<![CDATA[Reply to Do QGrahpicsItems need to be dynamicall allocated? on Tue, 28 Oct 2014 08:07:58 GMT]]>Ok, it's clearer now, I've misread your initial post…

What parameters are you giving that makes it fail ?

]]>https://forum.qt.io/post/249226https://forum.qt.io/post/249226Tue, 28 Oct 2014 08:07:58 GMT<![CDATA[Reply to Do QGrahpicsItems need to be dynamicall allocated? on Tue, 28 Oct 2014 00:25:31 GMT]]>When I do:
@A b(/parameters/)@
The complilation fails.

If I do:
@A b;@
(Using either default or no parameters), it works out fine.

And if I do:
@A *b = new A(/parameters/);@
It works fine.

]]>https://forum.qt.io/post/249209https://forum.qt.io/post/249209Tue, 28 Oct 2014 00:25:31 GMT<![CDATA[Reply to Do QGrahpicsItems need to be dynamicall allocated? on Tue, 28 Oct 2014 00:00:50 GMT]]>My question was not clear enough.

Can you post the code that is failing and then one that is successful ?

]]>https://forum.qt.io/post/249206https://forum.qt.io/post/249206Tue, 28 Oct 2014 00:00:50 GMT<![CDATA[Reply to Do QGrahpicsItems need to be dynamicall allocated? on Mon, 27 Oct 2014 00:01:42 GMT]]>The second one.

]]>https://forum.qt.io/post/249077https://forum.qt.io/post/249077Mon, 27 Oct 2014 00:01:42 GMT<![CDATA[Reply to Do QGrahpicsItems need to be dynamicall allocated? on Sun, 26 Oct 2014 20:40:25 GMT]]>Hi,

Do you mean something like:

@b = A@

vs

@b = A()@

?

]]>https://forum.qt.io/post/249048https://forum.qt.io/post/249048Sun, 26 Oct 2014 20:40:25 GMT